Polar RC3 GPS with Heart Rate Tracks your speed, distance and route using the latest GPS technology (SiRFstar IV) Slim and lightweight (58g) design with rechargeable battery and supersized digital display Unique Polar Smart Coaching features such as Running Index and Training Benefit analyze your run and guide your training to the next level (heart rate sensor included) Includes new Back to Start GPS feature that directs you back to your starting point in the shortest distance possible. Compatible with optional running and cycling sensors as well as polarpersonaltrainer.com, our free online training diary that allows you to share your training with friends